Hello newbphile,
I own both of those cans and both are great. As you most likely know the price difference is large, about $130 for the HD595s vs. $450-$500 for the HD650s. One thing Hi-end cans like the 650s will due is reveal a poor source 320kps mp3 through a n a/v receiver will probably leave you dissapointed, the HP circuit in most receivers are an afterthough by the manufacturer and not very good. Though I am sure it's much better than a stock soundcard. My reccomendation is similar to how I started out in this hobby. I would purchase the HD595s and take the difference in price of the 650s and improve your source. Get some software and rip your cd's into flac 24bit/96khz and get a entry level DAC/amp combo. Some examples; Fiio E7/E9 combo $199, Headroom total Bithead DAC/Amp $169, or something like the Grant Fidelity Tube DAC 09, it has a very good SS headphone amp built in as well as numerous inputs which would allow for expansion and upgrade. You can connect your computer using USB, optical or coax, and it is 24/96 compatible and has a tube buffer output stage as well. $240-$280. I have owned all of these at one time or another and was happy with all for their price points. Hope this helps!

I had the HD280 Pro a while ago and upgraded to the HD650 (amplified by a FiiO E7/E9) and the difference is absolutely massive. I've listened to a lot of high end headphones and I think the HD650 is the finest headphone under $1,000, period. If the price is ok, I would definitely suggest you try them. You can order them from headphone.com and send them back within 30 days if you decide you don't like them, I did that with 3 or 4 different headphones before I got the HD650 and fell in love.

You mean 44.1hz and 16bit sense there CD's? IF you get either Id suggest getting a NuForce DAC/amp.

You can still see these headphones listed at the same price. A testament to their quality. After breaking them in at various levels with an adequate amp, I have to say I love these headphones. With some additional software to emulate cross-over of speakers and boost the low-mid frequencies the HD650s are highly recommended by me. Beware: They aren't good for regular use at all. These are meant to be used at home, for professional use or extreme enthusiasts. I try to use some good crossover plugin that adds some "room reverb" to emulate some ambience and stereo. In short, headphones rest on your ears while music is meant to create an atmosphere (ambience) in the room which requires the sound to travel some distance. When buying headphones for pleasure I highly recommend something with noise cancelling that are comfortable to listen to for a long time. The HD650s are open and offer absolutely no noise cancelling from other sounds. Some find them uncomfortable, I enjoy mine for extended use so I would disagree. In terms of amplification, a Macbook Pro with a 1/8th inch does fine however you won't be able to damage your hearing if you wanted and they will be slightly underpowered changing the frequency response and dynamics. I suggest breaking them in with enough power and then not worry to much about it if you're simply looking for high quality audio. If you wish to do professional referencing with them, then buy a DAC although most entry level ones will not have enough power to truly drive these bad boys. Their nominal impedance sits at 300 ohms. I would love to write a review for the blog :)